- Kernel - mailweb.openeuler.org

[PATCH OLK-6.6 0/2] Backport NI_RANDOM for 5.15
by Luo Gengkun 14 Oct '26

14 Oct '26

Peter Zijlstra (2): sched/fair: Proportional newidle balance sched/fair: More complex proportional newidle balance include/linux/sched/topology.h | 4 +++ kernel/sched/core.c | 3 ++ kernel/sched/fair.c | 66 +++++++++++++++++++++++++++++++--- kernel/sched/features.h | 6 ++++ kernel/sched/sched.h | 7 ++++ kernel/sched/topology.c | 9 +++++ 6 files changed, 91 insertions(+), 4 deletions(-) -- 2.34.1

1 2

[PATCH OLK-6.6 0/2] Backport NI_RANDOM for 5.15
by Luo Gengkun 14 Oct '26

14 Oct '26

Peter Zijlstra (2): sched/fair: Proportional newidle balance sched/fair: More complex proportional newidle balance include/linux/sched/topology.h | 4 +++ kernel/sched/core.c | 3 ++ kernel/sched/fair.c | 66 +++++++++++++++++++++++++++++++--- kernel/sched/features.h | 6 ++++ kernel/sched/sched.h | 7 ++++ kernel/sched/topology.c | 9 +++++ 6 files changed, 91 insertions(+), 4 deletions(-) -- 2.34.1

1 0

[PATCH OLK-6.6 NI_RANDOM patchs 0/2] Introduce NI_RANDOM for 5.15
by Luo Gengkun 13 Oct '26

13 Oct '26

Peter Zijlstra (2): sched/fair: Proportional newidle balance sched/fair: More complex proportional newidle balance include/linux/sched/topology.h | 4 +++ kernel/sched/core.c | 3 ++ kernel/sched/fair.c | 66 +++++++++++++++++++++++++++++++--- kernel/sched/features.h | 6 ++++ kernel/sched/sched.h | 7 ++++ kernel/sched/topology.c | 9 +++++ 6 files changed, 91 insertions(+), 4 deletions(-) -- 2.34.1

1 2

[PATCH OLK-6.6 0/2] CVE-2026-100074
by Pu Lehui 13 Oct '26

13 Oct '26

Kumar Kartikeya Dwivedi (1): bpf: Mark bpf_refcount field as unique Mykyta Yatsenko (1): bpf: refactor special field-type detection kernel/bpf/btf.c | 59 ++++++++++++++++++++++++------------------------ 1 file changed, 29 insertions(+), 30 deletions(-) -- 2.34.1

2 3

[PATCH OLK-6.6] bpf: check_cond_jmp_op(): properly infer if register is null
by Pu Lehui 13 Oct '26

13 Oct '26

From: Eduard Zingerman <eddyz87(a)gmail.com> mainline inclusion from mainline-v7.3-rc2 commit d3ef6c097ba078e1f8c7239d76a0ce8b61e75095 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/19697 CVE: CVE-2026-98134 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- Nicholas Carlini reported a bug when verifier can incorrectly infer that a pointer is non-null. The bug occurs when two pointers are compared and one of them has a type w/o PTR_MAYBE_NULL flag, but which allows a value to be NULL at runtime. Here is an example: // `a` is PTR_TO_MEM | MEM_RDONLY | PTR_UNTRUSTED // `a` is 0 at runtime. // `b` is PTR_TO_MAP_VALUE | PTR_MAYBE_NULL void *a = bpf_rdonly_cast(0, 0); int *b = bpf_map_lookup_elem(...); if (a == b) *b = 42; // verifier does not catch null pointer dereference This happens because of a special case in check_cond_jmp_op(), which attempts to strip PTR_MAYBE_NULL flags from pointer types, when processing comparisons like `rA == rB`, if either rA or rB can't be null. The non-null property is derived based on the absence of PTR_MAYBE_NULL flag on rA's or rB's type. But that is not sufficient for types like PTR_TO_MEM, as in the example. This patch replaces type_may_be_null() call with reg_not_null(), which contains an allowlist of types for which absence of PTR_MAYBE_NULL actually means that the value can't be NULL at runtime. At the moment, the list in the reg_not_null() omits two types for which PTR_MAYBE_NULL is applicable: PTR_TO_XDP_SOCK and PTR_TO_BUF. In order to remain backward compatible, and assuming that only comparison between pointers of the same type makes sense, this commit extends reg_not_null(). W/o such an extension e.g. verifier_jeq_infer_not_null/null_ptr_to_map_value fails. reg_not_null() can be extended further, but I deem that out of scope for the fix at hand. Explicit base_type(...) != PTR_TO_BTF_ID checks in the check_cond_jmp_op() can be removed with migration to reg_not_null(), but that is a behavioural change, as the special case would start matching for PTR_TO_BTF_ID that is also is_trusted_reg(). I omit the behavioural change from this commit. Fixes: befae75856ab ("bpf: propagate nullness information for reg to reg comparisons") Suggested-by: Nicholas Carlini <npc(a)anthropic.com> Signed-off-by: Eduard Zingerman <eddyz87(a)gmail.com> Link: https://lore.kernel.org/r/20260826-bug-029-bad-non-null-inference-v2-1-1367… Signed-off-by: Alexei Starovoitov <ast(a)kernel.org> Conflicts: kernel/bpf/verifier.c [reg_not_null has no env arg] Signed-off-by: Pu Lehui <pulehui(a)huawei.com> --- kernel/bpf/verifier.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index b796d985e420..55c470694a80 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -470,6 +470,8 @@ static bool reg_not_null(const struct bpf_reg_state *reg) type = base_type(type); return type == PTR_TO_SOCKET || type == PTR_TO_TCP_SOCK || + type == PTR_TO_XDP_SOCK || + type == PTR_TO_BUF || type == PTR_TO_MAP_VALUE || type == PTR_TO_MAP_KEY || type == PTR_TO_SOCK_COMMON || @@ -15170,7 +15172,6 @@ static int check_cond_jmp_op(struct bpf_verifier_env *env, */ if (!is_jmp32 && BPF_SRC(insn->code) == BPF_X && __is_pointer_value(false, src_reg) && __is_pointer_value(false, dst_reg) && - type_may_be_null(src_reg->type) != type_may_be_null(dst_reg->type) && base_type(src_reg->type) != PTR_TO_BTF_ID && base_type(dst_reg->type) != PTR_TO_BTF_ID) { eq_branch_regs = NULL; @@ -15186,9 +15187,11 @@ static int check_cond_jmp_op(struct bpf_verifier_env *env, break; } if (eq_branch_regs) { - if (type_may_be_null(src_reg->type)) + /* src == dst && dst != NULL => src != NULL */ + if (reg_not_null(dst_reg) && type_may_be_null(src_reg->type)) mark_ptr_not_null_reg(&eq_branch_regs[insn->src_reg]); - else + /* src == dst && src != NULL => dst != NULL */ + if (reg_not_null(src_reg) && type_may_be_null(dst_reg->type)) mark_ptr_not_null_reg(&eq_branch_regs[insn->dst_reg]); } } -- 2.34.1

2 1

[PATCH OLK-6.6] bpf: backtracking shouldn't clear outer frame R1-R5 for callbacks
by Pu Lehui 13 Oct '26

13 Oct '26

From: Eduard Zingerman <eddyz87(a)gmail.com> mainline inclusion from mainline-v7.3-rc2 commit e3e4f66cc4b72333d0886ae2673c360248987889 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/19752 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- When processing calls to bpf_loop() verifier marks R1 (and R4) as precise. R1 tracks loop iterations number and because of the 'callback_depth < R1' mechanics in check_helper_call() must be marked precise. However, precision propagation for R1 was broken, when bpf_loop() call was verified on a second iteration. Consider the following verification trace: - main: bpf_loop(nr_loops, callback ...) - callback: BPF_EXIT - main: bpf_loop(nr_loops, callback ...) - ... While the first visit of the call to bpf_loop() propagated R1 precision as expected, the second call to mark_chain_precision() in the check_helper_call() set R1, but it was immediately reset when backtrack_insn() processed preceding BPF_EXIT in the loop deleted in this patch. Because of that, the second visit of the call to bpf_loop() injected checkpoint with R1 not marked as precise. Which could trick the verifier into accepting unsafe programs. See the next patch for an example of such program. Commit is structured in a way to minimize conflicts when 'bpf' would be eventually merged with 'bpf-next'. Fixes: ab5cfac139ab ("bpf: verify callbacks as if they are called unknown number of times") Reported-by: Nicholas Carlini <npc(a)anthropic.com> Suggested-by: Nicholas Carlini <npc(a)anthropic.com> Signed-off-by: Eduard Zingerman <eddyz87(a)gmail.com> Link: https://lore.kernel.org/r/20260831-bug-015-backtrack-cb-args-precise-v1-1-6… Signed-off-by: Alexei Starovoitov <ast(a)kernel.org> Conflicts: kernel/bpf/verifier.c [ctx conflicts] Signed-off-by: Pu Lehui <pulehui(a)huawei.com> --- kernel/bpf/verifier.c | 37 +++++++++++++++++-------------------- 1 file changed, 17 insertions(+), 20 deletions(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index b796d985e420..98454d1d1358 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -3997,37 +3997,34 @@ static int backtrack_insn(struct bpf_verifier_env *env, int idx, int subseq_idx, return -EFAULT; } } else if (opcode == BPF_EXIT) { - bool r0_precise; + bool from_subprog_call, r0_precise; + + /* BPF_EXIT in subprog or callback always returns + * right after the call instruction, so by checking + * whether the instruction at subseq_idx-1 is subprog + * call or not we can distinguish actual exit from + * *subprog* from exit from *callback*. In the former + * case, we need to propagate r0 precision, if + * necessary. In the former we never do that. + */ + from_subprog_call = subseq_idx - 1 >= 0 && + bpf_pseudo_call(&env->prog->insnsi[subseq_idx - 1]); + + r0_precise = from_subprog_call && bt_is_reg_set(bt, BPF_REG_0); /* Backtracking to a nested function call, 'idx' is a part of * the inner frame 'subseq_idx' is a part of the outer frame. * In case of a regular function call, instructions giving * precision to registers R1-R5 should have been found already. - * In case of a callback, it is ok to have R1-R5 marked for - * backtracking, as these registers are set by the function - * invoking callback. + * In case of a callback from bpf_loop(), R{1,4} in the calling + * frame would be set as precise and that is correct. */ - if (subseq_idx >= 0 && calls_callback(env, subseq_idx)) - for (i = BPF_REG_1; i <= BPF_REG_5; i++) - bt_clear_reg(bt, i); - if (bt_reg_mask(bt) & BPF_REGMASK_ARGS) { + if (from_subprog_call && (bt_reg_mask(bt) & BPF_REGMASK_ARGS)) { verbose(env, "BUG regs %x\n", bt_reg_mask(bt)); WARN_ONCE(1, "verifier backtracking bug"); return -EFAULT; } - /* BPF_EXIT in subprog or callback always returns - * right after the call instruction, so by checking - * whether the instruction at subseq_idx-1 is subprog - * call or not we can distinguish actual exit from - * *subprog* from exit from *callback*. In the former - * case, we need to propagate r0 precision, if - * necessary. In the former we never do that. - */ - r0_precise = subseq_idx - 1 >= 0 && - bpf_pseudo_call(&env->prog->insnsi[subseq_idx - 1]) && - bt_is_reg_set(bt, BPF_REG_0); - bt_clear_reg(bt, BPF_REG_0); if (bt_subprog_enter(bt)) return -EFAULT; -- 2.34.1

2 1

[PATCH OLK-6.6 0/2] Fix the perf tool cs-etm-decoder compilation issue
by Tengda Wu 13 Oct '26

13 Oct '26

Fix the perf tool cs-etm-decoder compilation issue. This issue was introduced by the stable-v6.6.157 version and has not yet been resolved, so temporarily revert it as a workaround. Tengda Wu (2): Revert "perf cs-etm: Fix thread leaks on trace queue init failure" Revert "perf cs-etm: Queue context packets for frontend" .../perf/util/cs-etm-decoder/cs-etm-decoder.c | 21 +- tools/perf/util/cs-etm.c | 240 +++++++----------- tools/perf/util/cs-etm.h | 8 +- 3 files changed, 102 insertions(+), 167 deletions(-) -- 2.34.1

2 3

[PATCH OLK-6.6 0/2] Fix the perf tool cs-etm-decoder compilation issue.
by Tengda Wu 13 Oct '26

13 Oct '26

Fix the perf tool cs-etm-decoder compilation issue. This issue was introduced by the stable-v6.6.157 version and has not yet been resolved, so temporarily revert it as a workaround. Tengda Wu (2): Revert "perf cs-etm: Fix thread leaks on trace queue init failure" Revert "perf cs-etm: Queue context packets for frontend" .../perf/util/cs-etm-decoder/cs-etm-decoder.c | 21 +- tools/perf/util/cs-etm.c | 240 +++++++----------- tools/perf/util/cs-etm.h | 8 +- 3 files changed, 102 insertions(+), 167 deletions(-) -- 2.34.1

2 3

[PATCH OLK-6.6 0/2] CVE-2026-100074
by Pu Lehui 13 Oct '26

13 Oct '26

Kumar Kartikeya Dwivedi (1): bpf: Mark bpf_refcount field as unique Mykyta Yatsenko (1): bpf: refactor special field-type detection kernel/bpf/btf.c | 59 ++++++++++++++++++++++++------------------------ 1 file changed, 29 insertions(+), 30 deletions(-) -- 2.34.1

2 3

[PATCH OLK-6.6] mm/huge_memory: fix unconditional pgtable deposit for special huge PMD in copy_huge_pmd()
by Jinjiang Tu 13 Oct '26

13 Oct '26

hulk inclusion category: bugfix bugzilla: https://atomgit.com/openeuler/kernel/issues/10116 -------------------------------- In copy_huge_pmd(), the special huge PMD path unconditionally allocates a pgtable and deposits it to the destination PMD. However, the pgtable withdraw in zap_huge_pmd() is guarded by arch_needs_pgtable_deposit(), which returns false on x86. This asymmetry causes a 4KB pgtable page and an mm->nr_ptes counter increment to leak on every fork+zap cycle of a special huge PMD on x86. Guard the deposit for special huge PMD in copy_huge_pmd() with the same arch_needs_pgtable_deposit() check, matching what vmf_insert_pfn_pmd() already does at insertion time and what zap_huge_pmd() does at teardown. Fixes: 923e224a1246 ("mm: introduce remap_pfn_range_try_pmd() for PMD-level hugepage mapping") Signed-off-by: Jinjiang Tu <tujinjiang(a)huawei.com> --- mm/huge_memory.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 805a903d8423..d423824dc67a 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1834,9 +1834,11 @@ int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm, pmd = pmdp_get_lockless(src_pmd); if (unlikely(pmd_present(pmd) && pmd_special(pmd))) { - pgtable = pte_alloc_one(dst_mm); - if (unlikely(!pgtable)) - goto out; + if (arch_needs_pgtable_deposit(dst_vma)) { + pgtable = pte_alloc_one(dst_mm); + if (unlikely(!pgtable)) + goto out; + } dst_ptl = pmd_lock(dst_mm, dst_pmd); src_ptl = pmd_lockptr(src_mm, src_pmd); spin_lock_nested(src_ptl, SINGLE_DEPTH_NESTING); @@ -1854,8 +1856,10 @@ int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm, /* dax won't reach here, it will be intercepted at vma_needs_copy() */ VM_WARN_ON_ONCE(vma_is_dax(src_vma)); - mm_inc_nr_ptes(dst_mm); - pgtable_trans_huge_deposit(dst_mm, dst_pmd, pgtable); + if (pgtable) { + mm_inc_nr_ptes(dst_mm); + pgtable_trans_huge_deposit(dst_mm, dst_pmd, pgtable); + } goto set_pmd; } -- 2.43.0

2 1